1. Field of the Invention
The present invention relates to a method to control hydrocarbon after treatment device temperature for an electronic control heavy duty compression ignition engine having an Electronic Control Module (ECM) during cold start conditions.
The present invention further relates to a method of modifying engine operating conditions during cold start conditions to raise after treatment temperature at a pre-determined rate to a temperature sufficient to permit controlled oxidation of said hydrocarbons in said after treatment device.
The present invention further relates to a method to operate an electronically controlled heavy duty diesel engine during cold start conditions to burn excess hydrocarbons from a diesel particulate filter in a controlled manner to prevent damage to the after treatment system.
2. Detailed Description of the Related Art.
Li et al., U.S. Patent Pub. No. 2007/0056554, discloses a method of reducing nitrogen oxides and particulate matter in compression ignition engine emissions. The method includes monitoring at least one engine sensor that generates a signal and response to at least one engine operating condition and adjusting at least one engine control parameter in response to the signal in such that in cylinder spatial distribution of equivalence ratio and temperature is substantially maintained to an operating region. The operating region corresponds to a set of equivalence ratios with respect to temperature values that are substantially outside regions supportive of NOx and particulate matter formation. The temperature valves are lower than 1,650 degrees Kelvin and the equivalent ratios are greater than about 0.5.
Sisken et al., U.S. Patent Pub. No. 2006/0218897, discloses a method, system and controller for increasing exhaust gas temperatures through controlled operation of a radiator fan in order to facilitate regeneration and particulate of a particulate filter. The method system and controller are applicable in systems having an engine which emits exhaust gases having particulates which are captured by a particulate filter.
Grau et al., U.S. Pat. No. 6,892,705, discloses a method for operating an internal combustion engine which includes using the injection pressure to control combustion in the engine to minimize exhaust gas emissions during a cold start or during a warm up phase.
Hawkins et al., U.S. Pat. No. 6,523,525, discloses an engine control system and method of controlling an internal combustion engine having mandatory engine warm up. The engine control system includes an ECM having a torque inhibit circuit and a speed inhibit circuit and at least one engine fluid temperature sensor in communication with the electrical communication with the torque inhibit circuit and the speed inhibit circuit of the ECM. The sensor is exposed to at least one engine fluid and is adapted to provide an inhibit signal to the torque inhibit circuit and to the speed inhibit circuit indicative of the temperature of the fluid within the engine. Torque inhibit circuit and speed inhibit circuit are operable to cause the ECM to disregard any requests from an operator commanding an increase in engine torque or engine speed until such times inhibit signals from the temperature sensors exceed a predetermined threshold.
Bhargava et al., U.S. Pat. No. 6,092,496, discloses a method of operating a diesel engine that includes sensing the temperature level associated with the engine. The method includes positioning an intake valve in an open position during the exhaust stroke of the engine if the temperature is below a predetermined threshold so that heated exhaust gases advance into the intake conduit during the exhaust stroke so as to heat the intake air located in the intake conduit prior to the intake air advancing into the combustion chamber. The method further includes the step of positioning an intake valve in a closed position during the exhaust stroke if the temperature level is above the predetermined threshold value so that the heated exhaust gases are prevented from advancing into the intake conduit during the exhaust stroke.